Thread-cutting tool.



B. BURDEN. THREAD CUTTING 'roo APPLICATION FILED JAN.20, M108.

attache;

passed through slots tinrrn stares reagent caries BRADFORD BORDEN, OF WARREN, OHIO, ASSIGNOR TO THE BORlDEN COMPA NY, OF WARREN,

' I OHIO, CORPORATION OF OHIO.

'rnnnan-cnmrne'roon Specification oi Letters Patent.

Patented June 8, 1909.

Application filed Januaryfid, 1908. Serial No. 411,705.

To all whom it may concern:

Be it known that l, BRADFORD BORDEN, of Warren, in the county of Trumbull and State of Ohio, have invented certain new and use- 5 ful Improvements in Thread-(jutting Tools;

and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the artto which it appertains to make and use the same.

The primary object of this invention is to enable both right and left hand threads to be cut by a single tool, and the invention is especially adapted for that class of tools by which taper threads are formed on pipes and the like.

The invention will be hereinafter fully set -forth and particularly pointed out in the claims.

In the accompanyinig, drawings, Figure 1 is a plan view of a three 'ing tool in connection with which my improvements may be employed. Fig. 2 is a side view, partly in section. Fig. 3 shows a double feed block. Fig. 4 shows the samedetached.

Referring to the drawings, 1 designates the housing; 2 the tubular sleeve extending rearwardly therefrom; 3 the chasers; a. the posts mounted on a collar 5- and having diagonal tension forms a leader screw, with a right-- hand thread 8 and a loft-hand thread 9. Each threaded portion consists of about three or four threads, and with each portion a separate feed engage,- These feed blocks may be moved into'engagement with and disengaged from. their res ective screw threads, being held to the wor holder 12 by retaining screws 13 in the blocks. ltis preferable, however, to employ a single teed lock, located at one side of the machine,

guideways with which engage logs of the block 10 may be caused towith threads at each end, (as at 10 Fig; 3) since in the use of two separate blocks there is danger that the operator might fail to properly disengage the block not intended to be used. The leader screw is secured to sleeve 2 by rivets 14 which may be readily removed in the event a new leader screw is needed.

The threads of each portion of the screw are suliicient to start the chasers on the pipe to be threaded, and as the threading operatiqn continues the screw runs oh" the feed block with which it was in engagement, and the device as a whole feeds itself on the pipe by the grip of the chasers. It is not neces sary, therefore, that the leader screw extend over the entire length oi: the sleeve, but only suflicient to start the Chasers on their work. Once this is accomplished the use of leaderscrews and blocks is unnecessary, and as the housing travels toward the work holder the chaser-s will recede, thereby forming a taper thread. That portion of the leader screw extension 7 having the thread 9 is of slightly greater diameter than the threaded portion 8. The work holder 12is formed in sections united by screws 15 to permit the leader screw extension to be readily secured to or removed from sleeve 2.

I. claim as my' invention:

1. A thread cutting. tool comprising a housing having a sleeve, chasers mounted in said housing, a leader screw'carricd by said sleeve at the rear end thereof and having right and lefthand threads, a work and means mounted on said work holder having right and left hand threads to engage either thread of the loader screw while starting the engagement between the chasors and the pipe or article to be threaded.

holder,

sleeve at the rear end thereof and having right and left hand threads, 2. work holder, and a reversible l'ccd block oppositely threaded at its opposite ends for engaging the rospcctive threads of the leader screw.

3. A thread cutting tool comprising a housing having a sleeve, chascrs mounted in said housing, a leader screw carried by said sleeve at the rear end thereof and having fight and left hand Eh eads, a" werk holder, specificatien in-the' presence of two subscriband a, feed block slide I mounted on'said ing Witnesses. 1 work holder and reversibYe end for end, said -feed block being oppositely threaded on its O D BORDEN' 5 ogposite ends for engaging either thread of Witnesses: t e leader screw. ALBERT E. KNOX,

In testimonywhereof, I have signed this EDWARDL. MIDDLETON. 

